The hardest part of creating any documentary series is selecting just what materials can and cannot be included. The number of phenomenal stories, researchers, groups and agencies doing amazing work on these topics far outweighs the amount of screen time available for coverage. Here's your chance to plunge into some of the research we weren't able to showcase in depth (or at all) as well as discover some of the major groups and agencies involved in this vital issue.

West Nile Virus
West Nile virus is one of the more disturbing invasive species issues. This deadly virus from Uganda is carried by birds and spread by mosquitoes. First detected in the Western Hemisphere in 1999, it has spread rapidly across North America including 47 continental states and into Canada and Mexico.

Domino Effects of Invaders
Invasive species can work in insidious ways. A sobering chain of events has unfolded in Bodega Bay, 70 miles north of San Francisco. The recent appearance of an aggressive invader — the European green crab — has marked the decline of the important local clam populations. These local clams, it turns out, have been keeping another invader in check – the eastern gem clam. Without the local clams intact, the gem clams have suddenly become much more aggressive invaders.

Forecasting Invasions
One of the main goals of invasive species researchers is to prevent further invasions. Ideally they'd like to be able to forecast introductions, dispersal and impacts of invasive species on native species and ecosystems. To do this, researchers like David Lodge are harnessing a host of new tools from computer models to state-of-the-art statistical analyses to peer into the future.